The invention relates generally to devices for growing horticultural products hydroponically. These devices can be characterized in that the growing area contains an aggregate in which the product is grown. Liquid nutrient is supplied at predetermined intervals to nourish the vegetable, fruit, plant, etc.
Such systems are well known. Described in U.S. Pat. No. 3,323,253 is a hydroponic unit in which nutrient is fed to the bottom of the growing chamber. On the one hand this system minimizes plant disturbance while nourishing with a bottom feeding technique, additionally avoiding leaf spotting, etc., since the nutrient never touches the exposed portion of the plant, but this system is inefficient in that only the root structure extending to the nutrient is capable of assimilating the food. The remaining root structure goes mainly unused, and substantial difficulties can be experienced when a variety of plants having different root lengths are planted in the same unit, by virtue of this bottom feeding technique.